FEV1 (expressed as litres [L]) is a spirometric measure of lung function. FEV1 was measured 60 minutes after administration of study drug. The results are expressed as a percentage in relation to the baseline value.

To show that formoterol 4.5 μg and 9 μg twice daily are superior to placebo in Japanese and European COPD patients treated for 12 weeks by evaluation of FEV1 60 minutes post-dose as the primary outcome variable. [ Time Frame: evaluated 60 minutes post-dose for 12 weeks ] [ Designated as safety issue: No ]

Forced Vital Capacity (FVC) is a spirometric measure of lung function. FVC was measured 60 minutes after administration of study drug. The results are expressed as a percentage in relation to the baseline value

Lung function (FEV1) was measured before administrations of the study drug (pre-dose). The results are expressed as a percentage of mean FEV1 over visists 4-6 in relation to the baseline (visit 3) value

Lung function (FVC) was measured before administrations of the study drug (pre-dose). The results are expressed as a percentage of mean FEV1 over visists 4-6 in relation to the baseline (visit 3) value

Patients were asked to measure and record lung function (peak expiratory flow [PEF] measured in the morning). Average values over the last 10 days of the run-in period and the whole treatment period were calculated. The results are expressed as the change from the run-in period average value

Patients were asked to measure and record lung function (peak expiratory flow [PEF] measured in the evening). Average values over the last 10 days of the run-in period and the whole treatment period were calculated. The results are expressed as the change from the run-in period average value

Change in Night-time Awakenings Due to Symptoms [ Time Frame: run-in period up to 12 weeks ] [ Designated as safety issue: No ]

Patients were asked to record the night-time awakenings due to symptoms (scored from 0-4 with 4 being the most severe). Period averages over the last 10 days of the run-in period and the whole treatment period were calculated. The results are expressed as the change from the run-in period average value

Breathlessness [ Time Frame: run-in period up to 12 weeks ] [ Designated as safety issue: No ]

Patients were asked to record breathlessness (scored from 0-4 with 4 being the most severe). Period averages over the last 10 days of the run-in period and the whole treatment period were calculated. The results are expressed as the change from the run-in period average value

Cough [ Time Frame: run-in period up to 12 weeks ] [ Designated as safety issue: No ]

Patients were asked to record cough (scored from 0-4 with 4 being the most severe). Period averages over the last 10 days of the run-in period and the whole treatment period were calculated. The results are expressed as the change from the run-in period average value

Use of Reliever Medication [ Time Frame: 12 weeks (end of run-in to last visit) ] [ Designated as safety issue: No ]

Patients were asked to record reliever medication use. Period averages over the last 10 days of the run-in period and the whole treatment period were calculated. The results are expressed as the change from the run-in period average value

Patients were asked to complete the St George's Respiratory Questionnaire (SGRQ). Subscale symptom score ranges from 0 to 100% and measures the effect of respiratory symptoms, frequency, and severity on quality of life. A score of 0 indicates the best possible status. Results are expressed as the change from baseline score with a decrease in score indicating improvement.

Evaluate the onset of action of formoterol 4.5 μg and 9 μg using placebo as a control, by evaluation of FEV1 as the primary objective [ Time Frame: Evaluated 5 minutes post-dose at Visit 3 ] [ Designated as safety issue: No ]

Compare the effect of formoterol 4.5 μg twice daily to that of formoterol 9 μg twice daily by evaluation of the same primary and secondary variables as for the primary objective [ Time Frame: evaluated at each visit for 12 weeks ] [ Designated as safety issue: No ]

The purpose of this study is to show the efficacy and safety of formoterol for the maintenance treatment of patients with COPD compared with placebo in patients in Japan and in European countries during 12 weeks.